Nonstatic photographic film and film base therefor



Oct. 9,1928 7 1,687,041

P. c. SEEL NONSTATIC PHOTOGRAPHIC FILM AND. FILM BASE THEREFOR Filed Aug. 12, 1927 WZWiZIM laul 6557992;

INVENTOR,

Mi Ma A TTORNEY.

Patented Oct. 9, 1928.

UNITED STATES PATENT OFFICE.

PAUL C. SEEL, OF ROCHESTER, NEW YORK, ASSIGNOR T0 EASTMAN KODAK COMPANY, I OF ROCHESTER, NEW YORK, A. CORPORATION OF NEW YORK. V

NONSTATIG rnoroeimrnrc' FILM AND FILM BASE THEREFOR.

-Applicatio'n filed August 12, 1927. Serial no. 212568.

This invention relates to non-static photographic film. and tothe base or support thereof. One object of the invention is to provide such a film which will have the usual qualities required to meet commercial conditions and will have, in addition, the ability to prevent or greatly lessen defects due to electrical discharges whi h are customarily referred to asstatic markings; Other objects will hereinafterappear.

In the accomp'anying drawing, the single figure is a diagrammatic section, upon an enlarged scale, of a photographic antistatic film embodying my invention.

I have found'that a photographic film in which the light sensitive photographic layer, such as a gelatino-silver-halide emulsion, is carried by an electrifiable base or support. can be rendered substantially antistatic by providing itwith a layer or backing containing a paratoluene sulfonamid-formaldehyde... resin. This backing is on the face of the support opposite to the one carrying the emulsion. Only a very thin layer, relative to the thickness of'the support, is required to bring about the antistatic result. It is, therefore, compare 'tively ineizpensive to carry out my nvention.

In the preferred form of my invention, which will be described in detail by way of illustration, I dissolve 3 parts by weight of the paratoluene sulfonan'iid-formaldehyde resin in 97 parts by weight, of acetone. coated is then brought very rapidly into and out of contact with this solution. so as to evenly and thoroughly coat itwith a very thin layer. The-acetone rapidly evaporates, leaving a. sufficiently hard backing, and yet the acetone insures a strong bond between the paratoluene sulfonamid-formaldehyde resin and the pyroxylin or other electrifiable film support. Of course, in place of acetone, any other volatile solvent, common to the elef-trifiable support and the paratoluene sulfonamid-formaldehyde resin, can be employed.

Referring to the accompanying drawing,

The surfzre of the support to be- 1' is a light-sensitive photographic layer, such as a gelatino-silver halide emulsion, say a negative motion picture emulsion. 2 is the ,electrifiable film support, such as a transparent, flexible, strong, waterproof,

pvroxylin layerfllike that customarily ema polymer. it is permanently fusible and is soluble in the usual volatileorganic solvents, such as acetone, mentioned-above. Since static manifestations are most apt to occur upon developing motion picture negative film that has been exposed under particularly dry atmospheric conditions, my invention is at the present time of most utility in rendering suchfilm antistatic.

I Haying thus described my invention, what I cla1m as new and desire to secure by Letters Patent is: 1. A flexible, photographic film. comprising an electrifiable support carrying on one face'a light-sensitive photographic coating and on the other face an antistatic layer containing paratoluene sulfonamid-formaldehyde resin. 1

2. A flexible motion picture film comprismg a pyroxylin support carrying on one face a gelatino-silver'-halide emulsion and on the other face an antistatic layer containing paratoluene sulfonamid-formaldehyde resin.

3. A flexible, transparent, laminated support adapted to receive light-sensitive photographic coatings, which comprises a main nitrocellulose layer and a relatively thinner layer containing paratoluene sulfonamidformaldehyde resin.

Signed at Rochester, New York, this 4th day of August 1927.

PAUL C. SEEL. 

